1. Field of the Invention
The invention refers to a driving arrangement for driving cutting rolls, e.g. of a mining machine in which arrangement the cutting roll means is, in direction of the axis of rotation, subdivided into a plurality of axially adjoining sections or portions and the cutting roll portions are, for the purpose of reducing the distance of adjacent cutting roll portions at the drift faced of the ore vein or other rock arranged at an angle relative to the axial position within the area of the bearing means and the drive means.
2. Description of the Prior Art
Known driving arrangements for cutting rolls, for example the arrangement having become known from U.S. Pat. No. 4,225,189, provide for cutting rolls which are subdivided in the axial direction of the driving shaft, in which arrangement the central section, consisting of two cutting rolls, can be telescopically enlarged in its width. For this purpose, the carriers must laterally be expanded in a telescoping manner and, for the purpose of obtaining a narrow gearing rib at the drive connection and at the bearing support of the cutting head portions, both outer cutting heads are angularily designed. It is a drawback of such an arrangement that the capability of telescoping movement within the central area has the unavoidable consequence of laterally shifting the carriers. The space remaining laterally of the machine and behind the roll is, on account of the construction, restricted. Thus, there remains always only little space for consolidating work, in particular for placing anchors in proximity to the drift face. The rotary coupling between the roll portions arranged at an angle one relative to the other is effected by means of gear rims arranged on the circumference of the roll, and, on account of the dust-laden atmosphere in proximity to the drift face, this rotary coupling is subject to great water.
From U.S. Pat. No. 3,848,930, there has already become known a type of a driving arrangement, in which both of the outer roll portions are equally arranged at an angle relative to the central roll portion. The transmission of rotation for driving the outer roll portions is effected via a universal joint of the driving shaft and gearing traction must be arranged around the universal joint for preventing any overload of the articulated driving shaft at the universal joint. Such a construction permits only a cutting roll having a small outer width and, a telescoping means which has become known in other arrangements can not easily be realized in such an arrangement.